This invention relates to lubricating systems for automotive components and, more particularly, to a device whereby the turbo charger on a diesel-type truck engine may be lubricated from a cold start.
Diesel-fuel internal combustion automotive engines differ from gasoline engines in several major respects. Power is created in a gasoline-fueled internal combustion engine by vaporizing the gasoline, mixing it with air, and igniting the resulting mixture within a cylinder of the engine. The expanding gases from ignition force a piston within the cylinder downward to turn a crankshaft which, in turn, eventually drives the wheels of the vehicle. The mixing of gasoline with air is performed in the carburetor of the gasoline engine.
Air needed for combustion in diesel engines enters the engine by way of a turbo fan unit, commonly known as a turbo charger, which draws air in through an inlet and directs it to the engine, and ignition of the fuel occurs when the fuel-air mix is compressed within the cylinder. One such unit is manufactured by AiResearch, as model T12.
During operation, the compressor in the turbo unit rotates at high speeds of up to 120,000 r.p.m. and it has been found that the use of ordinary bearings on the compressor shaft is not feasible at such speeds. Accordingly, the compressor shaft is rotatably supported in aluminum bushings. Lubrication of the turbo unit during operation is critical to efficient operation and prevention of breakdowns caused by excessive wear of the aluminum bushings.
Present lubrication systems provide an oil take-off, most commonly from the oil filter of the vehicle, whereby oil circulating through the engine block is directed to the turbo via an oil conduit. Such a system does not provide efficient lubrication of the turbo unit when the engine is first started and the flow of oil is not yet established, or when the engine is used for prolonged periods of time in extremely cold temperatures, such as commonly incurred when making runs through mountainous areas. Under conditions of extreme cold, motor oil thickens, and it is often as long as three minutes after the engine has been started before the oil is warmed enough to reach the turbo unit.
The current trend toward smaller automobile engines has increased the desirability for use of turbo units on cars as well as trucks. Turbo units provide a way for such engines to operate with increased power under heavier loads by providing more fuel mixture to the engine.
The need exists, therefore, for an engine component lubricating system which provides an initial charge of lubricating oil upon starting of a cold engine, independent of the operation of the engine's oil pump. Means should also be provided to replenish the oil charge during normal operation of the engine when the engine's own lubrication system will provide lubrication for the component part involved. As herein contemplated, one such component is the turbo charging unit commonly found on diesel engines for trucks and the like.
Accordingly, the present invention has the following objects:
To provide turbo lubricating systems for turbo-equipped internal combustion engines which operate from a cold start;
To provide such systems in forms readily adaptable for installation on existing engines;
To provide such systems in forms utilizing a minimum of moving parts and operating hardware;
To provide such systems in forms which are self-priming;
To provide such systems in forms which provide lubricating oil for starting and which thereafter may be substantially bypassed during normal operation;
To provide such systems in forms providing for the preheating of lubricating oil; and
To provide such systems in forms which are simple and economical to manufacture, install and maintain.